The Gene Ontology (GO) Consortium is a collaboration among model organism database groups, genome annotation centers and others who are actively engaged in the annotation of genomes, genes and gene products. By sharing in the development and adoption of semantic standards, by contributing to a common data repository, and by disseminating our resources freely to the scientific community, we promote and enhance the ability of scientists to use all available information to further the understanding of human health and disease. The objectives of the GO Consortium are 1) to build and support ontologies for molecular function, biological process, cellular component and sequence features; 2) to support the annotation of genomes, genes and gene products to these ontologies by model organism databases, genome annotation centers and others; 3) to provide extensive open and public access to the ontologies, the gene product annotations and supporting tools and documentation via a common data resource and 4) extend our community through hosting Users Meetings, adding new database groups to the GO Consortium, and exploring innovative research that advances the GO Consortium's commitment to finding practical solutions to semantic integration issues. This renewal application proposes to support the continued development and use of the GO. Major extensions of the project in this granting period include the implementation of the GO in formal ontological language, the realization of an ontology for sequence features, and the inclusion of the GO as a component of the Unified Medical Language System (UMLS).